it seems you’ve created your own form for creating the posts so you’d just have to add in the input fields as you like them and in the submission you insert them in the proper custom meta field using either wordpress update_post_meta function or ACFs update_field function (check documentation).
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2022 was a big year for Advanced Custom Fields, with more capabilities, a new generation of ACF Blocks, a refreshed UI, and a new home. Our year in review post looks at advancements we’ve made and offers a glimpse of the future. https://t.co/HahJUCcyH4